The present invention relates to a spectacle frame and more particularly to hinges of a spectacle frame swingably connecting its bridge with its sides.
In conventional spectacle frames wearers often experience that machine screws connecting interconnecting elements respectively projecting from the stationary and swingable members of hinges of the spectacle frame, in particular, the machine screws of the right hand side hinge viewed from the wearer, are apt to come loose and unscrew due to the repeated folding and opening of the sides relative to the bridge.
This phenomenon is considered to be caused by the following reasons: In a conventional hinge comprising e.g. three interconnecting elements the machine screw of that side is generally introduced from the above in a hole formed in the uppermost interconnecting element of the stationary member of the hinge and a hole formed in the underlying interconnecting element of the swingable member to be screwed into the screwed hole formed in the lowermost interconnecting element of the stationary member, underlying the interconnecting element of the swingable member, so as to allow the swinging of the swingable member relative to the stationary member around the machine screw, and since the machine screw has such a relation with the respective interconnecting elements of both hinge members, when the swingable member is forced to swing relative to the stationary member as the side of the spectacle frame are swung relative to the bridge, the machine screw is forced to unscrew due to friction with the inner surface of the hole formed in the interconnecting element of the swingable member each time the sides are swung relative to the bridge.
Therefore, if such a friction occurring between the inner peripheries of the holes formed in the interconnecting elements of the swingable member and the outer periphery of the machine screw is reduced the unscrewing of the machine screw can be expected to be substantially retained.